The invention relates to an electro-hydraulic power steering system, for an automobile with a steering wheel, rotationally connected with a steering column, intended for determining the orientation of the steered wheels of the vehicle, through a steering device with an integrated hydraulic cylinder the system having a booster pump rotated by an electric motor controlled by a computer as a function of a signal representing the speed of the vehicle and a signal representing the rate of steering wheel angle change.
In known systems of this type, the signal representing the rate of steering wheel angle change is provided by an angle sensor. These known systems have the disadvantage that the presence of such a sensor considerably increases the cost of the system.